low voltage logic family???

[albert]

Good Day all,

I need to do a battery operated project, my hope is that I can have it
run on low voltage and consume small power from the batteries. I need
a few basic gates and a binary counter with multiple outputs (such as
the 4060). Since computers run on low voltagethese days, I am hoping
that some vendor has a low voltage logic family.

Besides giving up and going with 5 volt cmos and ttl, does anyone have
suggestions?

Thanks

Al

 

[albert]

PIC chips run very nicely on 2 volts. If you clock them slowly, they
consume only about 100 microamps.

A PIC might work, but I would need a low power programmable VCO in
order to consider a PIC. Maybe I should be looking into low power
VCO's.

 

[Jim Thompson]

Good Day all,

I need to do a battery operated project, my hope is that I can have it
run on low voltage and consume small power from the batteries. I need
a few basic gates and a binary counter with multiple outputs (such as
the 4060). Since computers run on low voltagethese days, I am hoping
that some vendor has a low voltage logic family.

Besides giving up and going with 5 volt cmos and ttl, does anyone have
suggestions?

Thanks

Al

Though not spec'd that low, most 'HC parts will run at two volts, or
less (but slower tP, tR and tF). Just experiment.

...Jim Thompson

 

[Luhan Monat]

Good Day all,

I need to do a battery operated project, my hope is that I can have it
run on low voltage and consume small power from the batteries. I need
a few basic gates and a binary counter with multiple outputs (such as
the 4060). Since computers run on low voltagethese days, I am hoping
that some vendor has a low voltage logic family.

Besides giving up and going with 5 volt cmos and ttl, does anyone have
suggestions?

Thanks

Al

PIC chips run very nicely on 2 volts. If you clock them slowly, they
consume only about 100 microamps.

 

[Greg Pierce]

Good Day all,

I need to do a battery operated project, my hope is that I can have it run
on low voltage and consume small power from the batteries. I need a few
basic gates and a binary counter with multiple outputs (such as the 4060).
Since computers run on low voltagethese days, I am hoping that some vendor
has a low voltage logic family.

Besides giving up and going with 5 volt cmos and ttl, does anyone have
suggestions?

Thanks

Al

Use the 74LVCC family.

 

[Spehro Pefhany]

Good Day all,

I need to do a battery operated project, my hope is that I can have it
run on low voltage and consume small power from the batteries. I need
a few basic gates and a binary counter with multiple outputs (such as
the 4060). Since computers run on low voltagethese days, I am hoping
that some vendor has a low voltage logic family.

Besides giving up and going with 5 volt cmos and ttl, does anyone have
suggestions?

TI's MSP430 line of 16 bit micros will run on 1.8V and < 1uA, if you
run them at watch-crystal frequencies.

Best regards,
Spehro Pefhany

 

[albert]

Thanks Greg,

But I can't find any reference to that family of chips. I checked
findchips.com for 74lvcc00 and 74lvcc04 and got no matches.

I checked google for 74lvcc04, and got nothing (no matches and no
alternative suggestions).

Who makes the 74lvcc family???

I've checked TI and Maxim (Maxim is my favorite low power chipmaker).
At this time, I can only find 75HC and CD4000 series cmos-and neither
of them are spec'd below 5 volts.

I'd like to go to 2 volts, but would be happy enough at 3 volts.

You got any vendors for the 74LVCC family?

Thanks,

Al

 

[Greg Pierce]

Thanks Greg,

But I can't find any reference to that family of chips. I checked
findchips.com for 74lvcc00 and 74lvcc04 and got no matches.

I checked google for 74lvcc04, and got nothing (no matches and no
alternative suggestions).

Who makes the 74lvcc family???

I've checked TI and Maxim (Maxim is my favorite low power chipmaker). At
this time, I can only find 75HC and CD4000 series cmos-and neither of them
are spec'd below 5 volts.

I'd like to go to 2 volts, but would be happy enough at 3 volts.

You got any vendors for the 74LVCC family?

OOPS! My bad. It appears that the only devices in this family are octal
bus transcievers...

Try the TI 74LVCxxx family. Philips and Fairchild also have low voltage
logic families.

Here is TI's page for the 74LVC04:
http://focus.ti.com/docs/prod/folders/print/sn74lvcu04a.html

 

[albert]

OK, thanks.

I assume the lowest output frequency of the vco would be limited by
the clock frequency of the PIC xtal.

Here's some more info on my needs.

I need a VCO to operate between 75 KHz (upper limit) and 66 Khz (lower
limit) based on the output from an error amp. The output of the
project will be 250v p-p sine wave (near sine wave) @ 1 ua to 100 ua.
It has to have decent efficiency at low and medium load currents.

The VCO will drive a resonant piezoelectric transformer, the VCO will
vary it's output frequency in order to provide more or less power
output by driving the PZT closer/further from it's resonant frequency.

Can a VCO in software provide very small changes in output frequency
when the PIC is clocked at 36 Khz (approx half the desired vco output
frequency)?

Thanks,

Al

 

[Luhan Monat]

A PIC might work, but I would need a low power programmable VCO in
order to consider a PIC. Maybe I should be looking into low power
VCO's.

You may be able to do a VCO in software in a pic (PIC12F675) which has a
10 bit a/d. Could you explain just what you are trying to do? Not the
specific part of the project, but the whole thing.

 

[albert]

TI's MSP430 line of 16 bit micros will run on 1.8V and < 1uA, if you
run them at watch-crystal frequencies.

Hi Spehro,

I've read your posts for awhile on usenet and on the PIC mailing list,
thanks for the suggestion.

The 1 ua with a 36 Khz clock souns great!! Here's the rub...

I need a VCO to operate in the 77 to 66 Khz range, based on the output
of an error amp. This is for a requlated power supply based on a piezo
transformer. Can the MPS430 frovide a varaible output frequency in
that frequency range when clocked at 36 Khz???

Thanks,

Al

 

[albert]

OOPS! My bad. It appears that the only devices in this family are octal
bus transcievers...

Try the TI 74LVCxxx family. Philips and Fairchild also have low voltage
logic families.

Here is TI's page for the 74LVC04:
http://focus.ti.com/docs/prod/folders/print/sn74lvcu04a.html

WOW, the 74LVC looks like a winner! I'm pleased to see the low power
consumption, fast switching times and outsptanding drive capability
(source/sink 24 ma). It's almost too good to be true.

Thanks!

Al

 

[Spehro Pefhany]

Hi Spehro,

I've read your posts for awhile on usenet and on the PIC mailing list,
thanks for the suggestion.

The 1 ua with a 36 Khz clock souns great!! Here's the rub...

I need a VCO to operate in the 77 to 66 Khz range, based on the output
of an error amp. This is for a requlated power supply based on a piezo
transformer. Can the MPS430 frovide a varaible output frequency in
that frequency range when clocked at 36 Khz???

Not with such a slow clock. It could be done with higher clock
frequency (and proportionally higher current draw, at somewhat higher
voltage), but if all you need is a VCO, it probably wouldn't be the
best solution. Could you use a TLC551 (more like a couple hundred uA
at 2V)?

Best regards,
Spehro Pefhany

 

[Mark Jones]

In news:[email protected] (albert):

WOW, the 74LVC looks like a winner! I'm pleased to see the low power
consumption, fast switching times and outsptanding drive capability
(source/sink 24 ma). It's almost too good to be true.

Thanks!

Al

Hi Al, you can search all these datasheets for your needs. Good luck.
http://www.datasheetcatalog.com/

 

[Pooh Bear]

Good Day all,

I need to do a battery operated project, my hope is that I can have it
run on low voltage and consume small power from the batteries. I need
a few basic gates and a binary counter with multiple outputs (such as
the 4060). Since computers run on low voltagethese days, I am hoping
that some vendor has a low voltage logic family.

Besides giving up and going with 5 volt cmos and ttl, does anyone have
suggestions?

Low voltage Cmos. 74LV series IIRC.


Graham

 

[Pooh Bear]

Thanks Greg,

But I can't find any reference to that family of chips. I checked
findchips.com for 74lvcc00 and 74lvcc04 and got no matches.

I checked google for 74lvcc04, and got nothing (no matches and no
alternative suggestions).

Who makes the 74lvcc family???

I've checked TI and Maxim (Maxim is my favorite low power chipmaker).
At this time, I can only find 75HC and CD4000 series cmos-and neither
of them are spec'd below 5 volts.

I'd like to go to 2 volts, but would be happy enough at 3 volts.

You got any vendors for the 74LVCC family?

Google 74LV00 for example ! Forget the CC bit.

Tons of vendors.


Graham

 

[Pooh Bear]

OK, thanks.

I assume the lowest output frequency of the vco would be limited by
the clock frequency of the PIC xtal.

Here's some more info on my needs.

I need a VCO to operate between 75 KHz (upper limit) and 66 Khz (lower
limit) based on the output from an error amp. The output of the
project will be 250v p-p sine wave (near sine wave) @ 1 ua to 100 ua.
It has to have decent efficiency at low and medium load currents.

The VCO will drive a resonant piezoelectric transformer, the VCO will
vary it's output frequency in order to provide more or less power
output by driving the PZT closer/further from it's resonant frequency.

Can a VCO in software provide very small changes in output frequency
when the PIC is clocked at 36 Khz (approx half the desired vco output
frequency)?

I prefer the 8051 family.

Check this out.

http://www.semiconductors.philips.com/pip/P87LPC767HD.html

Onboard A-D can sense your error voltage. Use one of the counter/timers to
provide the VCO out.

With an Fout that high, you'll be running the part at close to full power
though ( 3mA @ 2.7V @ 10MHz ). You could look at ...

http://www.semiconductors.philips.com/pip/P87LPC769HD.html

and use the DAC out to drive an external VCO. Then you could run the micro at
slow clock / low power.

Damn - It'll consume *under* 10uA @ 2.7V @ 20kHz clock !

How fast does your VCO need to slew ?


Graham

 

[Mark Mcmillan]

OK, thanks.

I assume the lowest output frequency of the vco would be limited by
the clock frequency of the PIC xtal.

More like the upper freq.

Here's some more info on my needs.

I need a VCO to operate between 75 KHz (upper limit) and 66 Khz (lower
limit) based on the output from an error amp. The output of the
project will be 250v p-p sine wave (near sine wave) @ 1 ua to 100 ua.
It has to have decent efficiency at low and medium load currents.

The VCO will drive a resonant piezoelectric transformer, the VCO will
vary it's output frequency in order to provide more or less power
output by driving the PZT closer/further from it's resonant frequency.

Can a VCO in software provide very small changes in output frequency
when the PIC is clocked at 36 Khz (approx half the desired vco output
frequency)?

No but you can use a 4046 (PLL) and counter to generate higher freq. from a
lower freq. all though your best bet is to use a much higher clock freq.
frequency for the PIC.
You can also use a R2R ladder network (D/A) driven by the PIC and the VCO in
the 4046 to generate the wanted freq. the only problem is the temperature
and voltage stability of the VCO if the loop is open.

 

[Martin Riddle]

You might want to look at the tiny logic too if your really frugal with gate counts.

Cheers